advances.sciencemag.org/cgi/content/full/7/9/eabf2474/DC1

Supplementary Materials for

Ardipithecus hand provides evidence that humans and chimpanzees evolved

from an ancestor with suspensory adaptations

Thomas C. Prang*, Kristen Ramirez, Mark Grabowski, Scott A. Williams

*Corresponding author. Email: prang@tamu.edu

Published 24 February 2021, Sci. Adv. 7, eabf2474 (2021)

DOI: 10.1126/sciadv.abf2474

This PDF file includes:

Figs. S1 to S11 Tables S1 to S11

Supplementary Materials

Supplementary Text

PCA (17 variable dataset)

The first principal component (PC1) accounts for 61% of the variance and is positively

associated with the lengths of the proximal phalanx, intermediate phalanx, and fourth

metacarpal, and negatively associated with the fourth metacarpal mediolateral midshaft breadth

(table S2). PC2 accounts for 11% of the variance and is positively associated with proximal

phalanx mediolateral and dorsopalmar midshaft dimensions, and negatively associated with the

midshaft mediolateral breadth and head mediolateral breadth of the fourth metacarpal (table S2).

Hominoids and atelines are separated from cercopithecoids and other platyrrhines along PC2.

PC3 accounts for 8% of the variance and is positively associated with fourth metacarpal length,

fourth metacarpal midshaft mediolateral breadth, proximal phalanx midshaft mediolateral and

dorsopalmar dimensions. Fossil Australopithecus (A.L. 333, MH2) and Homo (DH1, SH4) hands

fall within the overlapping distributions of H. sapiens, G. gorilla, and G. beringei along PC1 and

PC2, and within the H. sapiens distribution along PC1 and PC3 (fig. S5b). However, A.L. 333 is

positioned just above the H. sapiens distribution and within the lower part of the G. gorilla

distribution along PC3 due to increases in the intrinsic length and midshaft mediolateral breadth

of the fourth metacarpal (fig. S5a).

CVA/DFA

The first canonical axis (CAN1), which separates humans and gorillas from other groups,

is negatively associated with the PP3 length, MC1 length, and MC1 base mediolateral breadth,

and positively associated with PP3 base mediolateral breadth, MC1 midshaft mediolateral

breadth, and MC5 length (table S5). The second canonical axis (CAN2), which separates

hominoids from other groups, is positively associated with the dorsopalmar dimensions of the

PP3 base and trochlea, and negatively associated with PP3 length and PP3 base mediolateral

breadth (table S5). The third canonical axis (CAN3) is positively associated with MC5 length

and PP3 midshaft mediolateral breadth, and negatively associated with MC1 length, PP3 trochlea

mediolateral breadth, and IP3 base dorsopalmar depth (table S5). Misclassifications most

frequently occur among cercopithecoid and platyrrhine individuals, but two Gorilla individuals

were misclassified as ‘Pan’ and ‘papionin’.

Fig. S1. Principal Components Analysis (PCA) on 26 logged geometric mean-standardized variables representing hand shape. (A) Principal Components 1 and 2. (B) Principal Components 1 and 3. Ar. ramidus is most similar to African apes, whereas Au. afarensis (A.L. 333), Au .sediba (MH2), H. naledi (DH1), and H. neanderthalensis (SH4) fall with modern humans. However, note that Ar. ramidus falls to the left of the Pan distribution along PC1 towards later hominins, indicating a slightly intrinsically shorter hand in Ar. ramidus compared to Pan. Furthermore, although Au. afarensis is most similar to modern humans, it falls intermediately between terrestrial mountain gorillas and modern humans along PC1.

Fig. S2. PCA loadings. (A) Loadings for the first principal component. (B) Loadings for the second principal component. (C) Loadings for the third principal component. MC1 = first

metacarpal, MC5 = fifth metacarpal, PP3 = third proximal phalanx, IP3 = third intermediate phalanx.

Fig. S3. Principal components boxplots computed from PCA on 26-variable dataset. (A) Principal Component 1. (B) Principal Component 2. (C) Principal Component 3.

Fig. S4. UPGMA cluster analysis on hand shape. The analysis is based on Euclidean distances calculated from the first three components of a PCA on 26 logged geometric mean-standardized variables representing hand shape. Ar. ramidus clusters with Pan and Pongo, whereas all later hominins cluster with modern humans.

Fig. S5. Principal Components Analysis (PCA) on 17 logged geometric-mean standardized variables including Hispanopithecus laietanus. (A) Principal Components 1 and 2. (B) Principal Components 1 and 3.

Fig. S6. Principal components boxplots computed from PCA on 17-variable dataset including H. laietanus. (A) Principal Component 1. (B) Principal Component 2. (C) Principal Component 3.

Fig. S7. Canonical Variates Analysis (CVA) on 26 logged geometric-mean standardized variables. (A) CAN1 and CAN2. (B) CAN 1 and CAN3. Ar. ramidus is classified as Pan, whereas all other hominins are classified as Homo.

Fig. S8. The relationship between pollical variables and hand size estimated using ordinary least-squares regression. (A) First metacarpal head depth (HDP). (B) First metacarpal head breadth. (C) Square-root of the first metacarpal base area. (D) Square-root of the first metacarpal diaphyseal cross-sectional area. Hand size is computed as the geometric mean of 26 measurements taken on metacarpals and phalanges. Ar. ramidus is most similar to Pan. Au. afarensis is most similar to Homo but has a relatively narrower MC1 head. Au. sediba is most similar to Homo but has a slightly smaller MC1 base and diaphysis; H. naledi is most similar to Homo but has an extremely small MC1 base; H. neanderthalensis is most similar to Homo but has a slightly wider MC1 head. Homo, grey circles; Pan, purple circles; Gorilla, green circles; Pongo, orange circles; Hylobates, blue circles; Papionins, red circles.

Fig. S9. Alternative evolutionary hypotheses for the relationship between multivariate hand shape, positional behavior and hand posture in anthropoid primates. (A) H1 (arboreal, semiterrestrial, terrestrial, and non-locomotor regimes). (B) H2 (arboreal, semiterrestrial, terrestrial, non-locomotor, and suspension regimes). (C) H3 (palmigrady, digitigrady, knuckle-walking, non-locomotor, and suspension regimes). (D) H4 (alternative palmigrady, digitigrady, knuckle-walking, non-locomotor, and suspension regimes). Branch colors correspond to hypothetical selective regimes. The best-fitting model according to information criteria is H3.

Fig. S10. Simulation results for comparisons of distributions of the likelihood ratio statistic computed using a Monte Carlo method. The light grey distributions represent the simpler of the two models whereas the dark grey distributions represent the more complex models. The vertical line represents the empirical likelihood ratio statistic. All models can be distinguished given our dataset and phylogenetic tree.

Fig. S11. The evolution of anthropoid hand shape according to SURFACE (17 variable dataset). (A) Phylogenetic tree with branches painted according to selective regime. (B) Species means for PC1 and PC2 (small circles) and estimated phenotypic optima (large circles). (C) Species means for PC1 and PC3 (small circles) and estimated phenotypic optima (large circles). Ar. ramidus was placed in the same selective regime as P. troglodytes and P. paniscus whereas H. laietanus was placed in a convergent selective regime with Pongo, Lagothrix, and Ateles.

Table S1. Principal Components Analysis loadings (26 variables) PC1 PC2 PC3 Standard deviation 0.54 0.31 0.29 Proportion of Variance 0.47 0.16 0.13 MC1 L 0.117 -0.413 0.215 MC1 BML -0.172 -0.245 0.140 MC1 BDP -0.127 -0.183 -0.117 MC1 MSML -0.363 -0.151 -0.328 MC1 MSDP -0.242 -0.184 -0.241 MC1 HML -0.254 -0.349 0.072 MC1 HDP -0.204 -0.26 0.104 MC5 L 0.308 0.036 0.084 MC5 BML -0.204 0.232 0.434 MC5 BDP -0.132 0.303 0.241 MC5 MSML -0.156 0.294 -0.189 MC5 MSDP -0.041 0.127 0.201 MC5 HML -0.096 0.156 0.371 MC5 HDP 0.020 0.19 0.091 PP3 L 0.402 -0.177 0.126 PP3 BML -0.046 0.112 0.009 PP3 BDP 0.092 0.094 -0.158 PP3 MSML 0.060 0.244 -0.277 PP3 MSDP 0.095 0.108 -0.253 PP3 TML -0.002 0.077 -0.121 PP3 TDP 0.186 0.02 -0.167 IP3 L 0.449 -0.196 0.043 IP3 BML 0.038 0.087 -0.111 IP3 BDP 0.132 0.021 -0.128 IP3 TML 0.021 0.053 0.044 IP3 TDP 0.121 0.005 -0.085 L = length, BML = base mediolateral, BDP = base dorsopalmar, MSML = midshaft mediolateral, MSDP = midshaft mediolateral, HML = head mediolateral, HDP = head dorsopalmar; TML = trochlea mediolateral, TDP = trochlea dorsopalmar; All variables standardized by their combined geometric mean

Table S2. Principal Components Analysis loadings (17 variables) PC1 PC2 PC3 Standard deviation 0.38 0.16 0.14 Proportion of Variance 0.61 0.11 0.08 MC4 L 0.36 -0.16 0.36 MC4 MSML -0.31 -0.46 0.45 MC4 MSDP -0.19 0.03 -0.02 MC4 HML -0.19 -0.41 -0.03 MC4 HDP -0.07 -0.14 -0.05 PP3 L 0.5 -0.2 -0.05 PP3 BML -0.23 -0.11 -0.12 PP3 BDP -0.03 0.2 -0.09 PP3 MSML -0.14 0.42 0.5 PP3 MSDP -0.05 0.41 0.29 PP3 TML -0.16 0.07 -0.3 PP3 TDP 0.11 0.24 -0.06 IP3 L 0.55 -0.07 0.03 IP3 BML -0.11 0.1 -0.18 IP3 BDP 0.04 0.15 -0.25 IP3 TML -0.12 -0.16 -0.19 IP3 TDP 0.03 0.09 -0.28 L = length, BML = base mediolateral, BDP = base dorsopalmar, MSML = midshaft mediolateral, MSDP = midshaft mediolateral, HML = head mediolateral, HDP = head dorsopalmar; TML = trochlea mediolateral, TDP = trochlea dorsopalmar; All variables standardized by their combined geometric mean

Table S3. Posterior probabilities of group membership using cross-validation

Homo Pan Gorilla Pongo Hylobatids Papionins OWM Atelids NWM Homo 67 0 0 0 0 0 0 0 0

% 100.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Pan 0 62 0 0 0 0 0 0 0 % 0.0 100.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

Gorilla 0 1 57 0 0 1 0 0 0 % 0.0 1.7 96.6 0.0 0.0 1.7 0.0 0.0 0.0

Pongo 0 0 0 33 0 0 0 0 0 % 0.0 0.0 0.0 100.0 0.0 0.0 0.0 0.0 0.0

Hylobatids 0 0 0 0 54 0 0 0 0 % 0.0 0.0 0.0 0.0 100.0 0.0 0.0 0.0 0.0

Papionins 0 0 0 0 0 51 2 0 1 % 0.0 0.0 0.0 0.0 0.0 94.4 3.7 0.0 1.9

OWM 0 0 0 0 0 2 23 2 2 % 0.0 0.0 0.0 0.0 0.0 6.9 79.3 6.9 6.9

Atelids 0 0 0 0 0 0 0 31.0 1 % 0.0 0.0 0.0 0.0 0.0 0.0 0.0 96.9 3.1

NWM 0 0 0 0 0 0 0 0 26.0 % 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 100.0

Table S4. Posterior probabilities of group membership for fossil hominin hands

taxon Homo Pan Gorilla Pongo Hylobatids Papionins OWM Atelids NWM

Ardipithecus ramidus 0.29 0.54 0.08 0.08 0.00 0.00 0.00 0.00 0.00

Australopithecus afarensis 1 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Australopithecus sediba 1 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Homo neanderthalensis 1 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Homo naledi 1 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Table S5. Coefficients of linear discriminants for canonical variates analysis (CVA)

CAN1 CAN2 CAN3 Proportion of trace 0.40 0.30 0.11 MC1 L -7.42 -4.49 -8.43 MC1 BML -4.25 -2.9 4.59 MC1 BDP 0.56 0.94 -4.06 MC1 MSML 5.82 3.09 -2.32 MC1 MSDP 0.39 1.64 -2.22 MC1 HML 0.55 1.38 1.29 MC1 HDP 0.47 -0.27 1.58 MC5 L 4.69 5.95 10.09 MC5 BML 0.44 -3.39 0.82 MC5 BDP 0.22 -1.32 1.45 MC5 MSML 0.34 -0.29 -1.36 MC5 MSDP -1.91 -2.59 -1.26 MC5 HML -0.07 -2.92 -0.28 MC5 HDP 1.88 -2.34 -0.02 PP3 L -10.09 -6.74 -2.42 PP3 BML 8.14 -10.4 -2.86 PP3 BDP 0.08 9.59 0.89 PP3 MSML -1.47 3.8 5.91 PP3 MSDP -0.89 -1.31 0.33 PP3 TML 0.76 3.3 -5.4 PP3 TDP -0.84 6.94 0.19 IP3 L 0.41 2.48 0.83 IP3 BML 3.88 1.3 0.47 IP3 BDP -0.28 2.39 -5.52 IP3 TML 1.38 -2.66 2.66 IP3 TDP -3.97 -0.45 -4.97

Table S6. Performance of alternative models for the evolution of the anthropoid hand H1 H2 H3 H4 SURFACE HBM HOU1

AIC -38.87 -59.30 -117.34 -83.17 -267.38 -15.94 -24.04 AICc -32.79 -51.25 -106.98 -72.81 -239.81 -14.84 -21.01 SIC 27.47 16.52 -32.05 2.13 -134.70 12.49 23.34 dof 21 24 27 27 42 9 15

Table S7. Evolutionary modeling parameters and phenotypic optima estimated by SURFACE PC1 PC2 PC3 α 0.960 0.550 149.910 σ2 0.018 0.011 1.435 t1/2 0.722 1.260 0.005 θ1 0.11 -0.01 0.32 θ2 0.75 -0.46 -0.12 θ3 1.50 1.23 0.64 θ4 1.24 0.95 0.34 θ5 -0.83 -0.18 -0.08 θ6 0.13 0.05 -0.31 θ7 -0.19 -0.09 0.36 θ8 0.30 0.09 -0.04 θ9 0.52 0.49 0.44 θ10 -0.33 0.37 -0.25 θ11 -0.43 0.15 0.49 θ1: Callicebus, Pithecia, Chiropotes, Aotus, Lagothrix, Alouatta, Trachypithecus; θ2: Nomascus, Hylobates, Symphalangus, Hoolock; θ3: Brachyteles; θ4: Ateles; θ5: Australopithecus, Homo; θ6: Ardipithecus, Pan; θ7: Macaca, Lophocebus, Mandrillus, Cercocebus; θ8: Pongo; θ9: Colobus; θ10: Gorilla

Table S8. Evolutionary modeling parameters and phenotypic optima estimated by SURFACE (17 variable dataset) PC1 PC2 PC3 α 9.953 12.128 10.946 σ2 0.249 0.070 0.063 t1/2 0.070 0.060 0.070 θ1 -0.015 -0.265 0.105 θ2 0.535 -0.16 -0.245 θ3 0.286 -0.057 0.017 θ4 0.022 -0.242 -0.093 θ5 -0.458 0.055 -0.201 θ6 -0.452 0.13 0.162 θ7 0.642 0.094 0.016 θ8 -0.499 -0.259 0.201 θ9 -0.085 0.079 -0.008 θ1: Trachypithecus, Nasalis, Colobus, Semnopithecus, Macaca, Mandrillus, Cercocebus, Lophocebus, Cercopithecus; θ2: Brachyteles; θ3: Pongo, Hispanopithecus, Ateles, Lagothrix; θ4: Alouatta, Cebus, Chiropotes, Pithecia; θ5: Australopithecus sediba, Homo; θ6: Gorilla; θ7: Hylobates, Hoolock, Symphalangus, Nomascus; θ8: Papio, Theropithecus; θ9: Australopithecus afarensis, Ardipithecus, Pan

Table S9. pGLS analysis of anthropoid hand proportions relative to body massa

trait estimate t p logLik AIC R2 λ MC1 32.9 -61.8 0.60 0.85 β0 2.58 ± 0.12 21.5 < 0.001 βlog(body mass) 0.28 ± 0.03 9.2 < 0.001 MC5 24.1 -44.1 0.57 1.00 β0 2.80 ± 0.21 13.3 < 0.001 βlog(body mass) 0.36 ± 0.04 8.7 < 0.001 PP3 23.9 -43.9 0.42 0.96 β0 2.92 ± 0.18 16.5 < 0.001 βlog(body mass) 0.25 ± 0.04 6.4 < 0.001 IP3 17.5 -31.0 0.34 0.98 β0 2.55 ± 0.21 12.1 < 0.001 βlog(body mass) 0.25 ± 0.05 5.5 < 0.001 aMC1 = first metacarpal length, MC5 = fifth metacarpal length, PP3 = third proximal phalanx length, IP3 = third intermediate phalanx length

Table S10. Extant sample size and composition (26 variable dataset)

Taxon AMNH CMNH FMNH HERC NYU MCZ MVZ PAHMA RMCA USNM TOTAL

Homo sapiens 12 38 3 14 67

Pan troglodytes 14 23 7 44

Pan paniscus 2 16 18

Gorilla beringei beringei 4 3 6 13

Gorilla beringei graueri 1 2 7 10

Gorilla gorilla 7 18 1 3 3 2 2 36

Pongo abelii 4 4

Pongo pygmaeus 6 5 2 1 4 11 29

Hoolock hoolock 6 1 1 8

Hylobates agilis 3 1 1 5

Hylobates klossii 3 2 5

Hylobates lar 1 20 2 1 24

Hylobates muelleri 1 1 2

Nomascus concolor 2 1 3

Symphalangus syndactylus 1 1 5 7

Cercocebus spp. 1 2 2 5

Mandrillus sphinx 4 1 2 1 2 10

Mandrillus leucophaeus 3 3

Lophocebus sp. 1 2 1 1 1 6

Macaca maura 1 1

Macaca mulatta 1 1

Macaca nigra 1 1

Macaca nemestrina 4 2 6

Macaca fascicularis 4 2 6

Papio cynocephalus 1 1 2

Papio hamadryas 1 4 5

Papio anubis 1 1

Papio papio 1 1

Theropithecus gelada 2 4 6

Cercopithecus mitis 2 2 4

Miopithecus talapoin 4 4

Chlorocebus aethiops 2 2

Colobus polykomos 1 2 3

Semnopithecus entellus 5 1 6

Nasalis larvatus 5 5

Trachypithecus cristatus 5 5

Table S10 (continued). Extant sample size and composition (26 variable dataset)

Ateles paniscus 1 1

Ateles fusciceps 2 2

Ateles geoffroyi 1 2 2 5

Ateles belzebuth 3 3

Alouatta seniculus 3 1 4

Alouatta caraya 1 1

Alouatta palliata 1 4 5

Brachyteles arachnoides 1 1

Lagothrix lagotricha 2 4 1 3 10

Cebus capucinus 1 1

Cebus apella 2 2 4

Cebus olivaceus 6 6

Saimiri sp. 6 1 7

Aotus sp. 2 2

Pithecia sp. 1 1

Chiropotes sp. 3 1 4

Callicebus sp. 1 1

Total 87 91 46 5 16 58 23 14 30 46 416 AMNH = American Museum of Natural History; CMNH = Cleveland Museum of Natural History; FMNH = Field Museum of Natural History; HERC = Human Evolutionary Research Center, University of California, Berkeley; NYU = New York University; MCZ = Museum of Comparative Zoology, Harvard University; MVZ = Museum of Vertebrate Zoology, University of California, Berkeley; PAHMA = Phoebe A. Hearst Museum of Anthropology, University of California, Berkeley; RMCA = Royal Museum for Central Africa; USNM = United States National Museum, Smithsonian

Table S11. Extant sample size and composition (17 variable dataset)

Taxon AMNH CMNH FMNH HERC NYU MCZ MVZ PAHMA RMCA USNM TOTAL

Homo sapiens 13 39 3 13 68

Pan troglodytes 15 23 7 45

Pan paniscus 2 16 18

Gorilla beringei 4 2 5 11

Gorilla gorilla 7 17 1 3 3 2 2 35

Pongo abelii 4 4

Pongo pygmaeus 6 7 1 3 11 28

Hoolock hoolock 6 1 1 8

Hylobates agilis 3 1 1 5

Hylobates klossii 3 2 5

Hylobates lar 1 20 2 1 24

Hylobates muelleri 1 1 2

Nomascus concolor 2 1 3

Symphalangus syndactylus 1 1 5 7

Cercocebus spp. 1 1 2 4

Mandrillus sphinx 3 1 2 1 2 9

Mandrillus leucophaeus 2 2

Lophocebus sp. 1 1 1 1 1 5

Macaca maura 1 1

Macaca mulatta 1 1

Macaca nigra 1 1

Macaca nemestrina 4 2 6

Macaca fascicularis 3 2 5

Papio cynocephalus 1 1

Papio hamadryas 4 4

Theropithecus gelada 2 4 6

Cercopithecus mitis 2 2

Colobus polykomos 1 2 3

Semnopithecus entellus 1 1

Nasalis larvatus 5 5

Trachypithecus cristatus 4 4

Ateles paniscus 1 1

Table S11 (continued). Extant sample size and composition (17 variable dataset)

Ateles fusciceps 1 6 7

Ateles geoffroyi 1 2 3 6

Ateles belzebuth 3 3

Alouatta seniculus 3 1 4

Alouatta caraya 1 1

Alouatta palliata 1 3 4

Brachyteles arachnoides 1 1

Lagothrix lagotricha 2 3 1 3 9

Cebus capucinus 1 1

Cebus apella 2 2

Cebus olivaceus 5 5

Pithecia sp. 1 1

Chiropotes sp. 1 1

Total 87 93 16 5 7 53 24 13 22 49 369 AMNH = American Museum of Natural History; CMNH = Cleveland Museum of Natural History; FMNH = Field Museum of Natural History; HERC = Human Evolutionary Research Center, University of California, Berkeley; NYU = New York University; MCZ = Museum of Comparative Zoology, Harvard University; MVZ = Museum of Vertebrate Zoology, University of California, Berkeley; PAHMA = Phoebe A. Hearst Museum of Anthropology, University of California, Berkeley; RMCA = Royal Museum for Central Africa; USNM = United States National Museum, Smithsonian